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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
241

Landscope | Interpreting Environmental Consciousness

Humphrey, Jonah Thomson 13 June 2008 (has links)
This thesis proposes a way in which architecture and the built environment might work to integrate human consciousness and natural process. A theoretical design entitled Landscope is presented as a responsive, sustainable landscape that offers understanding of nature through active observation, interpretation and transformation of the environment. The design proposal is situated at the edge of Hamilton Harbour, Ontario, Canada, adjacent to the existing facilities of the National Water Research Institute. Two extended studies accompany the design proposal. The first, Water, presents a poetic exploration of cosmic, responsive, and connective qualities of water relating to nature and technology. The second study, Connected Fields, focuses on the visionary American engineer Buckminster Fuller and his ‘Geoscope’ project, a geodesic dome designed to act as a monitoring and control centre for global material and resource flows. This section also includes a discussion of general conceptions of the world, focusing on key twentieth-century conceptions of the Biosphere, Gaia, and the Noösphere. Historical theories of environmental perception are discussed including Gestalt psychology and technical systems of observation. Drawing upon this cultural material, the thesis attempts to open boundaries that separate nature and technology, encouraging a complex, mutually dependent relationship between these traditionally separate realms. The general pursuit is a cybernetic and virtual model for environmental and ontological hybridity, involving an evolution of consciousness at both individual and global scales.
242

Between Technological Flesh and the Technological Field: A phenomenology of the domestic interior

Patterson, Duncan 27 October 2009 (has links)
Swift and radical technological change necessitates a re-appraisal of the phenomenology of the house. Canonical phenomenology often has been technologically averse and the phenomenological appraisal of the house, as offered by philosopher Gaston Bachelard (1958) and architect Juhani Pallasmaa (1994), has notably omitted its technological components. This thesis asserts that neither the technologization of the flesh nor the field can be ignored. Upon asserting the importance of both technology and the house to our Being, the thesis proposes some basic principles for understanding technological change. A re-appraisal of the phenomenology of the house is then initiated, starting with a selected series of behavioural and symbolic foci: the hearth, the toilet, the table, the bed and the window. These are discussed with regard to their historical importance in the house and speculated upon as they become increasingly changed by advanced technology. This thesis takes the form of a book. It is a synthetic and removed work, navigating the overlapping zones of a number of disparate discourses. Its perspective is situated in the midst of many complex and interconnected metaphors. It is part historical description, poetical observation, philosophical conjecture, curation, and design.
243

Transient Rheology of Stimuli Responsive Hydrogels: Integrating Microrheology and Microfluidics

Sato, Jun 30 October 2006 (has links)
A new microrheology set-up is described, which allows us to quantitatively measure the transient rheological properties and microstructure of a variety of solvent-responsive complex fluids. The device was constructed by integrating particle tracking microrheology and microfluidics and offers unique experimental capabilities for performing solvent-response measurements on soft fragile materials without applying external shear forces. Transient analysis methods to quantitatively obtain rheological properties were also constructed, and guidelines for the trade-off between statistical validity and temporal resolution were developed to accurately capture physical transitions. With the new device and methodology, we successfully quantified the transient rheological and microstructural responses during gel formation and break-up, and viscosity changes of solvent-responsive complex fluids. The analysis method was expanded for heterogeneous samples, incorporating methods to quantify the microrheology of samples with broad distributions of individual particle dynamics. Transient microrheology measurements of fragile, heterogeneous, self-assembled block copolypeptide hydrogels revealed that solvent exchange via convective mixing and dialysis can lead to significantly different gel properties and that commonly applied sample preparation protocols for the characterization of soft biomaterials could lead to erroneous conclusions about microstructural dynamics. Systematic investigations by varying key parameters, like molecular structure, gel concentration, salt concentration, and tracer particle size for microrheology, revealed that subtle variations in molecular architecture can cause major structural and microrheological changes in response dynamics. Moreover, the results showed that the method can be applied for studying gel formation and breakup kinetics. The research in this thesis facilitates the design of solvent-responsive soft materials with appropriate microstructural dynamics for in vivo applications like tissue engineering and drug delivery, and can also be applied to study the effect of solvents on self-assembly mechanisms in other responsive soft materials, such as polymer solutions and colloidal dispersions.
244

The analysis of strategies that enterprises take in the financial crisis

Tsai, Hui-ju 18 July 2010 (has links)
During Nov.2008 to Apr. 2009, firms in Taiwan encountered dramatic financial crisis, and this impact made unemployment rate still climbing and economic depression. In order to reduce the impact from financial tsunami, every firm takes some strategies to resist it. The objective of our study is to find out the influence from financial tsunami on the listed companies. More importantly, we base on the three mechanisms (mimetic force, normative force and coercive force) of institutional theory and the perspectives of population theory to analyze why firms choose those strategies. We collect and analyze 201 returned questionnaires. We find when firms face both high market force, mimetic force and coercive, they tend to choose manipulation strategies. When firms face both low market force, mimetic force and coercive force, they tend to choose compromise strategies. When firms face high market force and low mimetic force and coercive force, they tend to use defiance strategies. When firms face low market force and high mimetic force and coercive force, they tend to use acquiescence strategies.
245

The analysis of strategies firms choose under the financial crisis-Evidence form stock exchange and OTC companies

Wen, Kai-hsiang 22 February 2011 (has links)
In 2008-2009, firms in Taiwan encountered dramatic financial tsunami, and this crisis made unemployment rate still climbing and economic depression. In order to reduce the impact from financial tsunami, every firm chooses some strategies to resist it. The purpose of our study is to find out the influence from financial tsunami on the listed companies. More importantly, we base on the three mechanisms (mimetic force, normative force and coercive force) of institutional theory to analyze the real reason for choosing strategies. We collect and analyze 201 returned questionnaires. The finding of this study is that the main factor of choosing strategies is from the mimetic force and normative force. In fact, the enterprise is affected by mimetic pressure deeply, and then it would tend to use the passive strategies. The enterprise is affected by normative pressure deeply, and then it would tend to use the active strategy. Interestingly, whether the enterprise is affected by coercive pressure or not, it doesn¡¦t affect the strategies choosing.
246

Complexing AIEE-Active Tetraphenylthiophene Fluorophore to Poly(N-Isopropyl acrylamide)

Lai, Yi-Wen 13 July 2012 (has links)
In this article, a multiple-responsive polymer micelles system was constructed by using ionic bond to link the hydrophobic tetraphenylthiophene (TP) fluorophores, which possess the property of aggregation-induced emission enhancement (AIEE), with the hydrophilic poly(N-isopropyl acrylamide) (PNIPAM). The susceptibility of the ionic ammonium-sulfonate (Am-Sul) bonds towards metal ions, acid and base triggered the AIEE-operative fluorescence (FL) response. To exercise the idea, PNIPAM with sulfonate terminal was primarily prepared to react with TP-derivatives functionalized with ammonium groups to generate polymer complex of TP-PNIPAM. When in water, the polymer complex TP-PNIPAM formed micelles with the aggregated TP core interconnecting the hydrophilic PNIPAM shell by the ionic Am-Sul bonds. With the operative AIEE effect, the aggregated TP core of the micelles fluoresced but upon the additions of metal ions, acid and base, the ionic bonds dissociated to result in the collapse of the micelles and the FL quenching. A novel fluorogenic sensor capable to respond to multi-stimuli was therefore constructed. Amphiphilic micelle systems with the hydrophilic poly(N-isopropyl amide) (PNIPAM) shell and the hydrophobic tetraphenylthiophene (TP), which has the novel aggregation-induced emission enhancement (AIEE) feature, core inter-connected by ionic bonds were prepared in this study to explore the AIEE-operative emission response towards critical micelle concentration (CMC) and lower critical solution temperature (LCST). To exercise the idea, TP functionalized ammonium cations and PNIPAM with terminal sulfonate group were individually prepared and mixed together to yield three amphiphilic TP-PNIPAM complexes with different hydrophobic TP to the hydrophilic PNIPAM (x/y) ratios. When in aqueous solution, TP-PNIPAMs form micelles with the aggregated TP core, which emits strongly due to the operative AIEE effect, encompassed by the PNIPAM shell. The resultant CMC and LCST of the TP-PNIPAM micelles can be varied by changing the hydrophobic to the hydrophilic x/y ratio and can be monitored by the AIEE-dominant fluorescence responses towards concentration and temperature variables.
247

Optimal Design of Demand-Responsive Feeder Transit Services

Li, Xiugang 2009 August 1900 (has links)
The general public considers Fixed-Route Transit (FRT) to be inconvenient while Demand-Responsive Transit (DRT) provides much of the desired flexibility with a door-to-door type of service. However, FRT is typically more cost efficient than DRT to deploy. Therefore, there is an increased interest in flexible transit services including all types of hybrid services that combine FRT and pure DRT. The demand-responsive feeder transit, also known as Demand-Responsive Connector (DRC), is a flexible transit service because it operates in a demand-responsive fashion within a service area and moves customers to/from a transfer point that connects to a FRT network. In this research we develop analytical models, validated by simulation, to design the DRC system. Feeder transit services are generally operated with a DRC policy which might be converted to a traditional FRT policy for higher demand. By using continuous approximations, we provide an analytical modeling framework to help planners and operators in their choice of the two policies. We compare utility functions of the two policies to derive rigorous analytical and approximate closed-form expressions of critical demand densities. They represent the switching conditions, that are functions of the parameters of each considered scenario, such as the geometry of the service area, the vehicle speed and also the weights assigned to each term contributing to the utility function: walking time, waiting time and riding time. We address the problem faced by planners in determining the optimal number of zones for dividing a service area. We develop analytical models representing the total cost functions balancing customer service quality and vehicle operating cost. We obtain close-form expressions for the FRT and approximation formulas for the DRC to determine the optimal number of zones. Finally we develop a real-case application with collected customer demand data and road network data of El Cenizo, Texas. With our analytical formulas, we obtain the optimal number of zones, and the times for switching FRT and DRC policies during a day. Simulation results considering the road network of El Cenizo demonstrate that our analytical formulas provide good estimates for practical use.
248

Examination of Teacher Efficacy and Culturally Responsive Beliefs of Alternative Certified and Traditionally Certified Hispanic Teachers Serving Hispanic Students in High Priority Schools

Coston, Wood Sights 2010 May 1900 (has links)
The purpose of this mixed method study was to examine teacher self efficacy and culturally responsive self efficacy of in-service Hispanic teachers teaching in high priority schools which serve large percentages of students of color with respect to the teachers' route to certification (alternative or traditional). This study also personal narratives to explore highly effective both alternatively and traditionally certified inservice teachers. The three guiding research questions for this mixed method study were: 1. What are teacher efficacy beliefs of alternatively certified teachers and traditionally certified Hispanic teachers who work in high priority schools serving Hispanic students? 2. What are culturally responsive beliefs of alternative certified teachers and traditionally certified Hispanic teachers who work in high priority schools serving Hispanic students? 3. What are the voices of highly effective alternative certified teachers and traditionally certified Hispanic teachers who work in high priority schools serving Hispanic students?Participants in the quantitative portion of the study were 90 middle and high school in-service teachers teaching in high priority schools in the Texas/Mexico borderlands of South Texas. The participants (N=4) in the qualitative portion of the study were purposively drawn from the quantitative participants. Findings of the study were derived from the use of two questionnaires (Teacher Self Efficacy Scale & Culturally Responsive Teacher Self Efficacy Scale) and an in-depth semi-structured interview with four participant in-service teachers. The major findings in this study were: 1. There are no significant differences in teacher self efficacy between alternatively certified teachers and traditionally certified teachers. 2. There are no significant differences in culturally responsive teacher self efficacy between alternatively certified teachers and traditionally certified teachers. 3. Sample population of Hispanic teachers scored themselves as having high teacher self efficacy and culturally responsive self efficacy. 4. The themes from teachers participating in the narrative portion of the study were: (a) high levels of teacher expectations, (b) effective school/parent relationships, (c) effective use of previous work experience, (d) utilization of the funds of knowledge of the students, (e) effective teacher/student connection, and (f) consistent use of self reflection.
249

Stimuli-responsive Polymers in Solution and on Grafted Surfaces

Fu, Hui 2010 May 1900 (has links)
Thermoresponsive polymers such as poly(N-isopropylacrylamide) (PNIPAM) have lower critical solution temperature (LCST) in aqueous solutions. Below the LCST, these polymers are hydrophilic with an extended coil conformation. Above the LCST, they undergo a sharp phase transition to form a collapsed hydrophobic conformation. The LCSTs are also affected by cosolutes and the effects of anions on LCSTs follow the Hofmeister series. We successfully used a simple digital melting point apparatus to study the effects of heating rates, solvent compositions, cosolutes, and redox state, on the LCSTs of thermoresponsive polymers. Moreover, the temperature range of the apparatus allowed for analyses at much higher temperatures and provides a simple way to examine irregular clouding behavior in more complex systems. Meanwhile, stimuli-responsive surfaces grafted with thermoresponsive polymers can switch from hydrophilic to hydrophobic thermally. As the LCST can be subsequently changed with the addition of salts, the salt effects on the wettability of these thermoresponsive surfaces will dramatically impact the surface performance. In this dissertation, I prepared PNIPAM/SiO2 nanocomposite surfaces by a covalent layer-by- layer assembly procedure and such surfaces were then used in studies of salts effects on surface wettability. Both the effects of anions and cations on the changes of advancing angles (Delta Theta a) of the PNIPAM/SiO2 nanocomposite surfaces were significant (Delta Theta a up to 90 degrees). The anion effects on the surface wettability followed the Hofmeister effect as expected. Parallel studies on solution showed that variation of cations had a large effect on the LCST of PNIPAM too. Moreover, analyses of the Theta a and LCST data using activity instead of using concentration showed different orders for the cation effects which were readily grouped by the cation charge numbers. No difference was seen for the anion effects in similar studies. AFM studies showed that surface morphology changes were correlated with the Delta Theta a.
250

Selected Texas Driver Education Instructors’ Feelings About A Driver Education Cultural Awareness Survey

Saint, Nina Jo 2011 May 1900 (has links)
This study examined what items driver education instructors felt should be included in a cultural awareness survey to assess instructors' preparedness to teach a culturally diverse student clientele. In addition, the study examined the ways driver education instructors felt a cultural awareness survey should be administered. The instrument used in the study was the Driver Education Cultural Awareness (DECA) Survey that consisted of 14 items. There were eighty-one (N = 81) participants in the study with forty-six (N = 46) from the Texas' Education Service Center, Region 4 area (Houston area) and thirty-five (N = 35) from the Texas' Education Service Center, Region 10 area (Dallas area). The findings of this study were: (1) Instructors believed that a survey instrument should include information about "preparedness to teach a culturally diverse student clientele," "men and women presented in equitable roles," and "images of teenager drivers;" and (2) Instructors did not agree on how a survey instrument should be administered.

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